A wind turbine blade usually comprises a composite laminate structure as load carrying structure. The composite laminate structure is typically manufactured using fibre reinforcing material embedded in a polymer matrix. The laminate structure is typically formed by a plurality of stacked fibre layers. Today, the fibre layers are mostly selected from glass fibres and carbon fibres.
The load carrying structure is typically manufactured by infusing stacked fibre layers with resin and curing or hardening the resin in order to form a composite structure. To aid the resin flow during infusion, a flow enhancing fabric may be needed between fibre layers. This is particularly the case for carbon fibres due to the small size of the fibres and hence the insufficient size of voids between the fibres to let resin flow. However, placing a conventional flow media isolates or separates each fibre layers from one another. The conventional flow media isolating the fibre layers results in significantly reducing the conductivity in between each carbon fibre layers. Thus when a lightning strikes the load carrying structure, despite the presence of a lightning protection system, the lighting current cannot be easily dissipated in the load carrying structure.
Thus, there is a need for a solution that provides both flow for the resin to be infused and conductivity through stacked fibre layers.